DESMIDIUM. 249 



D. qua rlfiTifj ultra Kiitz. Phyc. gerni. 1845, p. 141 ; De Toni, Syll. Als. 1889, 

 p. 780. 



/;// var. f/f;tJr<i ny/ilf/i t/i Roy & Biss. Scott. Desni. 1894, p. 9 ; 

 G. s. West, Alg. X. Ireland, 1902, p. oil. 



Differs from the typical form only in its quadrangular 

 vertical view, and consequent greater relative breadth 

 in the front view. 



Zygospore elliptical ; inner layer of membrane tawny. 



Length 24'8 ?JL ; breadth 57 '6-60^ ; length of zygo- 

 spore 47 \j. : breadth 32'5 u. 



ENGLAND. Ambleside (Rcdfs) and Loughrigg (Ben- 

 nett), Westmoreland. Penzance and Tremethick Moor, 

 Cornwall (Rolfs ; M<u'<ii'<iud). 



SCOTLAND.- -otston Moss ; Heughhead near Aboyne, 

 and Blackmoss in Cromar, Aberdeen (Rolfs ; Roy <C* 

 Biss.). Braemar, Aberdeen ! 



IRELAND. Slieve Donard. Down ! 



('COf/r. Dixlt'ilnili<ni.- -France. Germany. Switzerland. 

 Austria. Italv. Poland. Australia. E. Africa. Mada- 



i 



United States. Colombia. Brazil. Paraguay. 



Var. amblyodon (Itz.) Eabenh. (PL CLXV, % 7.) 



hi.-iiiiiduni' nntbbjrnlni Itz. iii llalx-nh. Bacill. Sachs, fasc. 7, 1852, no. io, 

 t. v, f. (i.l. 



I). Swartzii var. amblyodtm Halx-nh. Krypt.-fl. Sa.-hs. 1863, p. 181; Flor. 

 Europ. Alsr. 1868, p. 1.14; De Toni, Syll. A1-. 1889, p. 780; West, 

 Freshw. Alg. Maine, 1891, p. 354 ; Borge, Sao Paulo Alg. 1918, p. 75. 



Cells with lateral angles not obliquely truncate, but 

 distinctly and broadly rounded. Filaments often en- 

 closed in a mucous sheath. 



Length 15-20;ji ; breadth 32-50^; breadth of 

 isthmus 25-45 (i. 



IRELAND. --Xear Ballynahinch, Galway ! 



Geogr. Distribution. Germany. Sweden. United 

 States. Brazil. 



5. Desmidium cylindricum Grev. 

 (PL CLXIV, figs. 7-10.) 



Desmidium cyUndncum Grev. Scott. Crypt. Fl. 1827, vol. v, t. 293, vol. vi, 

 p. 38 ; in Hook. Brit. Flor. 1833, p. 402 ; Kiitz. Synops. Diat. 1834, 

 p. 86 ; Menegh. Synops. Desni. 1840, p. 4 (sep.) ; Ralfs in Ann. Mag. 



